The present invention concerns a device for an underpressure-activated dispensing valve in a pipe, for example a drinking straw. In its position of use, the pipe is intended for connection to a receptacle containing a fluid, for example a liquid food article, at a pressure P3. The pressure P3 in the receptacle may constitute an overpressure relative to the ambient pressure P1 of the receptacle and the pipe, for example atmospheric pressure or another pressure reference. The fluid and the receptacle, however, do not have to be overpressured relative to P1. The purpose of the present valve device is, among other things, to prevent unintended fluid outflow from the receptacle. For example, the receptacle may be shaped as a rigid drinking receptacle or a soft drinking bag.
Fluid outflow from the receptacle may be initiated by, for example, a person sucking in one end of the pipe, thus supplying the dispensing valve with a valve-activating and valve-opening underpressure P2 relative to said ambient pressure P1.
A similar valve device and associated method is disclosed in Norwegian patent application no. 20015957. The device according to this patent application comprises, among other things, an outer casing and an inner pipe being movable relative to each other. The inner pipe may be deformable or connected to a bellows. When the inner pipe is supplied an underpressure P2, it is moved relative to the outer casing, thereby allowing an outlet opening in the valve to open to fluid outflow from a drinking receptacle connected thereto. When the underpressure P2 ceases, the valve will close the outlet opening automatically, even at an overpressure P3 in the receptacle.
In some other known valve devices, opening and closing of the valve is carried out through manual and mechanical movement of the sealing element of the valve, Many such valves will open automatically at an overpressure P3 in the receptacle to which the valve is connected, which may cause unintended fluid outflow and spill. Therefore, such valves are used essentially for non-pressurized fluids, for example water.
Moreover, many of the known valve devices have a complex shape and manner of operation, and thus they may be relatively expensive to manufacture.